The Plague Riot happened in Moscow between September 15 and September 17, 1771 and was caused by an outbreak of bubonic plague.
The plague in Moscow appeared in late 1770, and became a major epidemic in the spring of 1771. The authorities created forced quarantines, destroyed contaminated property without compensation or control, and closed public baths.This caused fear and anger among the citizens. Many factories, markets, stores, and administrative buildings also closed down. Acute food shortages followed.
By early September, the rumors of an imminent uprising had already been circulating. The Archbishop Ambrosius of Moscow tried to prevent the citizens from gathering at the Icon of the Virgin Mary of Bogolyubovo in Kitai-gorod (as a quarantine measure), but this led to an immediate cause for the Plague Riot. On September 15, huge crowds of citizens began to flow towards the Red Square at the sound of the alarm bell. They burst into the Kremlin and destroyed the archbishop's residence and its wine cellars.
On September 16, the riot gained in strength. Angry citizens captured the Donskoy Monastery,and killed Archbishop Ambrosius.
Approximately 200,000 people died in Moscow and its outskirts during the plague.